Your questions answered: Fire and life safety

The Oct. 18, 2018, fire and life safety webcast presenters addressed questions not covered during the live event.

By William Koffel, PE, FSFPE and Joshua Greene, PE October 30, 2018

Fire detection, notification, and suppression systems are specified for the safety of the building’s occupants in the event of a fire. Fire and life safety systems need to be specified, installed, commissioned, and maintained, depending on each building type and location.

Codes and standards, including the International Fire Code and various NFPA standards, provide design and installation provisions for fire detection, notification, and suppression systems in the event of a fire or other emergency event.

Presenters William Koffel, PE, FSFPE, Koffel Associates, Columbia, Md., and Joshua Greene, PE, Simpson Gumpertz & Heger, Waltham, Mass., respond to questions not answered during the fire and life safety: detection, notification, and suppression systems webcast on Oct. 18, 2018.

Question: In what conditions and building types must fire protection and/or fire/smoke detection be installed above suspended ceilings of commercial buildings?

Bill Koffel: NFPA 13: Standard for the Installation of Sprinkler Systems contains requirements for sprinkler protection in some concealed spaces. The requirements are based on whether the concealed space is of combustible or non-combustible construction. Even in non-combustible spaces, sprinkler protection may be required depending on the fuel load in the concealed space.

Joshua Greene: Smoke detectors are required above suspended ceilings when a total coverage smoke detection system is required by the code. This is typically limited in today’s code environment, as total coverage smoke detection is usually not required in buildings that have sprinkler protection. There may be a few instances where an occupancy type would require total coverage and sprinklers are not required or provided. You may also encounter total coverage smoke detection when replacing an old fire alarm system in an existing building (health care, ambulatory care, detention and correctional, etc.) that doesn’t have sprinklers. In that case, the total coverage must be maintained.

Question: Explain interface requirements between fire alarm and fire suppression systems, and include preaction.

Greene: The fire alarm system is usually required to activate upon sprinkler water flow and also monitor the system, including control valves. For preaction and gaseous systems, it depends on how that system’s fire detection is being handled. If a separate releasing panel specifically for the suppression system is provided, the detectors that are part of the activation sequence report to that releasing panel and the fire alarm system does nothing more than monitor alarm, trouble and supervisor conditions from the releasing panel. If the main fire alarm system is also used as the releasing panel, the detectors for activating the suppression system are system detectors monitored by the fire alarm panel. The fire alarm system must be programmed to recognize those detectors as part of the suppression system release sequence so that they serve that duty in addition to being a system detector. In this scenario, it is very important to recognize that the fire alarm system has to carry a separate listing as a releasing panel.

Question: What is UUKL in reference to smoke control?

Greene: UUKL refers to Underwriters Laboratories’ (UL) product category for smoke control equipment. Equipment intended to be utilized as part of an engineered smoke control system must be listed as UUKL complain. Equipment with this listing have typically been evaluated in accordance with ANSI/UL 864, “Control Units and Accessories for Fire Alarm Systems.”

Question: I’m working with notification in ambient conditions with relative humidity above 95%. Do you have possible solutions? Almost of the brands doesn’t have solution for that condition.

Greene: Almost all major notification appliance manufacturers should have audible and visible notification appliances that are listed for outdoor use that should be appropriate for high humidity applications when installed properly with weatherproof back boxes and related electrical equipment. The appliances should be listed for outdoor use in accordance with UL 1638 (visible appliances) and UL 464 (audible appliances). I recommend discussing your particular needs with your local fire alarm equipment representatives, who should be able to identify products that meet your needs.

Question: I’m mainly interested in residential systems. Can you please talk about multi-family dwellings?

Koffel: Multi-family dwellings have the option of using NFPA 13 or NFPA 13R systems. The advantage of NFPA 13R is the ability to omit sprinklers from come concealed combustible spaces and areas in which fatal fires generally do not originate.

Question: Is it permissible for a non-UUKL listed fire alarm control panel (FACP) to monitor the status (alarm, trouble, supervisory contacts) of a UUKL smoke control system panel? Or does the main FACP need to be UUKL listed as well?

Koffel: Yes, it is permissible.

Question: What certification is required for an engineer preparing fire alarm construction drawings?

Koffel: NFPA 72: National Fire Alarm and Signaling Code contains qualification requirements for individuals who design fire alarm systems. However, one must also consult the state regulations with regard to the practice of engineering. In some states, fire protection system drawings are required to be prepared by or under the direct supervision of a registered professional engineer.

Question: Can you address system design requirements for renovation projects? Address this question from both a fire alarm and a suppression viewpoint.

Koffel: This is an area that has changed significantly over the past several years. The International Code Council (ICC) has the International Existing Building Code and NFPA 101: Life Safety Code has Chapter 43. There is no simple answer to this question. Depending on the level of work that is to be performed, fire alarm and suppression systems may need to be provided as required for new construction. In other instances, one may not be required to install fire alarm or suppression systems.

Greene: From fire alarm perspective, the code requirements will utilize the existing building code. For IBC jurisdictions, this is now handled through the International Existing Building Code. For jurisdictions adopting NFPA 101, Chapter 43 addresses these requirements. The extent of requirements will be based on the categorization of the renovation work (alterations, change of occupancy, new addition, etc.) and the extent of the work. It can range from providing code compliance in the new renovation area only with new devices connected back to the fire alarm system to an upgrade of the entire system because an occupancy change required features that the existing system cannot support.

Question: Is NFPA 914: Code for Fire Protection of Historic Structures a code or a standard?

Koffel: NFPA 914 is considered a code. Having said that, most jurisdictions do not adopt NFPA 914. Therefore, one gets to NFPA 914 as a reference document within the adopted code (i.e., Chapter 43 in NFPA 101) or as an alternative compliance method (also referred to as an equivalency).

Question: How does the fire alarm control panel (FACP) interface with a room emergency power off (EPO) switch?

Greene: The extent of interaction between a fire alarm system and an EPO switch should be based on a risk analysis of the specific facility or area and the resultant control sequence for equipment. There is no single answer to this question, as facilities having EPOs typically have operations that can be significantly impacted by an improperly designed EPO system. In some cases, detection of a fire can initiate an automatic sequence that includes activation of an EPO, but other operations prefer to handle EPO activation manually through a specific sequence of operation upon receipt of an alarm or through another method to avoid an inappropriate activation or introducing a single point of failure.

Question: Are sprinkler heads required above ceilings with lay-in tiles?

Koffel: NFPA 13 contains requirements for sprinkler protection in some concealed spaces. The requirements are based on whether the concealed space is of combustible or non-combustible construction. Even in non-combustible spaces, sprinkler protection may be required depending on the fuel load in the concealed space. Question: Where do fire doors fit into all these?

Koffel: Fire doors are a means to protect openings in walls required to have a fire resistance rating. They are part of the overall fire safety strategy but not directly related to fire alarm or fire suppression systems.

Question: Are submittal requirements the same for special hazards systems versus sprinkler systems, for example NFPA 2001: Standard on Clean Agent Fire Extinguishing Systems?

Koffel: Yes. Chapter 5 of NFPA 2001 contains a list of information that is required to be on shop drawings (working drawings). There is also a paragraph that refers to the specification and talks about what generally is considered design information.

Question: How do you address retrofit installations when the as-built drawings do not exist and the scope of work is device for device replacement only? Or even tenant build-out installations where only a small portion of the overall building and system installation is made available?

Koffel: With respect to fire alarm systems, NFPA 72 requires system documentation to be maintained on site. NFPA 13 does not have the same requirement although NFPA 25 refers to original acceptance information for some of the required tests. The simple answer is that one uses the information that is available. For example, if the hydraulic information sign is provided for the sprinkler system that information can be used as a basis for design.

Question: Are off-site notifications typically via FACP or building management system (BMS)?

Koffel: The FACP is the more common method for anything related to fire protection systems.

Question: My state lists what International Building Code (IBC) code is applicable, but how do I find out what NFPA codes are applicable? Do I just use the latest issued?

Koffel: Go to Chapter 35 and you will see a list of all reference standards and the edition that is referenced.

Question: Can a building fire alarm system always be used as a releasing panel for a suppression system?

Koffel: No, it needs to be listed for releasing service.

Question: What is your opinion of zone isolation valves in a system? We have large zones that take a long time to drain, which consumes a large amount of water and restricts the timing based on building operations.

Koffel: One needs to balance the potential negative impact (closed valves are the most common mode of sprinkler system failure) with the benefit of reducing the impact of any shut down of the system. For example, in covered malls, additional zone valves may be beneficial to reduce the impact of shutdowns associated with frequent tenant changes.

Question: What about the Ethernet-based fire alarm systems? For example, panels and sensors or modules communicating over Ethernet as opposed to hard-wiredwhat NFPA says about this?

Greene: The 2016 edition of NFPA 72 introduced the new Class N pathway (circuit) in Chapter 12 to specifically address ethernet type systems. Class N pathways have the following distinct requirements:

  • They must include two or more pathways where operational capability of the primary and a redundant pathway to a device must be verified through end to end communication
  • A loss of intended communications between endpoints is annunciated as a trouble signal
  • A single open, ground, short or combination of such faults on one pathway won’t affect other pathways
  • Conditions that affect the operation of the primary and redundant pathways such that the system’s minimum operational requirements cannot be achieved shall annunciate as a trouble condition
  • Primary and redundant pathways are not allowed to share traffic over the same physical segment

Question: Can you give examples of how having a sprinkler system might reduce quantity of, or substitute for, smoke detectors?

Koffel: There are numerous code provisions that reduce the requirement for smoke detection when a building is protected with an automatic sprinkler system. This typically applies to smoke detection in common spaces (such as corridors) but not smoke detection or smoke alarm requirements within a sleeping room. Another example is that NFPA 101 requires a manually-operated fire alarm system in new educational occupancies. The code then says that manual fire alarm boxes are not required if smoke detection is provided and then further states that smoke detection is not required when automatic sprinkler protection is provided.